tilecache_clean: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/sbin/tilecache_clean - from package: tilecache

You may install the required package with command apt-get install {package}

Error in other languages:
tilecache_clean: bevel nie gevind nie
tilecache_clean: comandă negăsită
tilecache_clean: comando não encontrado
tilecache_clean: commande introuvable
tilecache_clean: command not found
tilecache_clean: käsku ei ole
tilecache_clean: không tìm thấy lệnh
tilecache_clean: komanda nerasta
tilecache_clean: Kommando nicht gefunden.
tilecache_clean: kommandot finns inte
tilecache_clean: komut yok
tilecache_clean: nie znaleziono polecenia
tilecache_clean: níor aimsíodh an t-ordú
tilecache_clean: no se encontró la orden
tilecache_clean: no s'ha trobat l'ordre
tilecache_clean: opdracht niet gevonden
tilecache_clean: parancs nem található
tilecache_clean: perintah tidak ditemukan
tilecache_clean: príkaz nenájdený
tilecache_clean: příkaz nenalezen
tilecache_clean: команда не найдена
tilecache_clean: командата не е открита
tilecache_clean: 命令找不到
tilecache_clean: コマンドが見つかりません